Packing box



FIG. 1 is a perspective view of a packing box;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof; and

FIG. 6 is a top view thereof, the opposite side being a mirror image of the side shown herein; and,

FIG. 7 is an enlarged detail view of the lower side of FIG. 2.

The portion shown by broken lines is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a packing box, as shown and described. 